Creep Meters: A creep meter uses a wire stretched across the fault to measure movement of the ground. Laser-Ranging Devices: It uses a laser beam to detect fault movements. Tiltmeters: A tiltmeter measures the tilting of the ground. Satellite Monitors: The satellite bounces off radio waves off the ground.
Outline
Devices that Monitor Faults
There are four instruments that geologists put in place that measure stress and deformation in the crust.
Creep Meters
A creep meter uses a wire stretched across a fault to measure movement of the ground.
On the other side, the the wire is anchored to a post.
On the other side of the wire, it is attached to a weight that can slide if the fault moves.
Geologists can measure the amount the moved by measuring how much the weight have moved.
Laser-ranging devices
It uses a laser beam to detect tiny fault movements.
It calculates any change in the time needed for the laser beam to taavel to the reflector and back.
The device can detect change in the distance to the reflector.
Tiltmeters
It measures tilting of the ground.
A tiltmeter is like a carpenter's level.
There is two bulbs that are filled with a liquid and connected with a hollow stem.
Geologists fill the tiltmeter with water and if the land rises or falls, the water in the two bulbs will tilt.
Liquid will slightly flow from one bulb from another.
Each bulb contains a measuring scale to measure the depth of the bulbs.
Geologists read the scales to measure the amount occurring along any fault.
Satellite Monitors
Geologists use satellites equipped with radar to make images of faults.
The satellites bounces off radio waves off the ground.
The time it takes for the waves to make their round trip provides measurements of the distance to the ground.
Geologists compares changes of the ground taken at the same places, at the different time.
Monitoring Risk in the United States
Even with a lot of data, geologists can not predict accurately when and where an earthquake will strike.
Exactly what will happen during an earthquake is always uncertain.
Geologists do know where earthquakes are likely to happen.
Table of Contents
Monitoring Fault
Vocabulary
Creep Meters: A creep meter uses a wire stretched across the fault to measure movement of the ground.
Laser-Ranging Devices: It uses a laser beam to detect fault movements.
Tiltmeters: A tiltmeter measures the tilting of the ground.
Satellite Monitors: The satellite bounces off radio waves off the ground.
Outline
Devices that Monitor Faults
Monitoring Risk in the United States
Back to Homepage